Piston for explosion-engines



F. BETKE-H.

, PFSTONZFQR'EXPLOSION ENGINES. AAPPLICATION FILED DEc..s, l1919'.

1,373,291 y Patented Mall. 29, 1921.

PATENT oFFicE.

FREDERICK BETKER, 0F CLEVELAND, OHIO.

Sp'ecicaton of Letters Patent.

PISTON FOR EXB'JLOSION-ENGENES.V

Patented Mar. 29, 1921.

Application led December 8, 1919. Serial No. 843,442.

T all 'whom t Vmay concem:

Be it known that I, FPEDERICK BETKnn, a citizen of the United States, and resident of Cleveland, in the'county of VCuyahoga and State of Ohio,"hav'e invented certain new and useful Improvements inPistons for Exploi sion-Engines, of which I vhereby' declare the ffollowing to be a full, clear, and exact dev cranks revolve in the crank caseand which scription, such aS willl enable others skilled in the art to which it :appertains to make and use the saine.

- The obj ects of the invention are to provide means forpi-eventing the formation of carbon upon the inner face of the pst'on in an explosion engine.

This carbon when jarred by the vibration ofthe engine falls in iiakes into the crank pit and is broken up andcarried with the oil circulation into the.v enginebearings in hard gritty particles and causes them to loverheat and burn o ut. f

The Y carbon is derived from Vthe oil splashed upon the inside of thepiston as the is charred by contact with the wall of the piston as it becomes superheated by the high .temperature of the explosion in the cylinders.

The invention comprises an insulating agency interposed between the outer and inner Surfaces ofthe head of the piston which prevents or retards the conduction of heat therethrough so that the temperature of the inner surface can never attain a sufficiently high degree tofcarbonize the oil splashed upon it.

The insulating agency preferablyV comprises closed chambers intermediate `ofthe outer and inner-surfaces of the piston .head

thus limiting the area of conducting metal `to the thin marginal walls of the'piston.

Thischamber can be filled with heat resiSting, Vand insulating material such as a' paste of grease or mineral non Vheat conductlng substances or metal alloys by means of.

)which the temperature will be materially reduced at the inside surface of thepiston head side wall.

or the air can be exhausted to produce a vacuum in the'cylinder head byV means of which the very high temperature of the eX- plosion end of the cylinder can be prevented from passing through the piston head. The invention is illustrated in the accompanying drawings, where Figure l is a longitudinal section of a piston head; F ig. 2 is a similar view showing the chamber extended upon the sides.

In these views A is the piston head; B, the skirt, C pivot pin, A is a closed chamber in the piston head, which is provided with a closure, D, which must be air-tight in case a vacuum is to be produced in the chamber.

E is a sealing tube, through which the air is l drawn from this chamber-when a vacuum 1s' to be produced, and without which it would be impossible toproduce a vacuum in the vwall of the chamber and in Fie. 2 in the oiit- In F ig. 2 the sides .of the chamber are continued down the sides-or skirt of the piston thus materially cooling the inside wall surface.

Having described' the invention what` I claim as new and desire to secure by Letters Patent is: i

l. In a piston for an explosionengine, a chamber in the head thereof intermediate the outer and inner surfaces, a closure for said chamber, anda sealing tube passing` through said closure, through which air can be exhausted from said chamber.

2. In a piston for an'explosionengine, Vav

chamber in the head thereof, intermediate of its inner and outer surfaces saidV chamber continued into the sides of said piston, a closure for said chamber and a sealing tube p for said closure.

In testimony whereof, I hereunto set my hand this 25 day ofOctobei, 1919.

' FREDERICK BETKER. In presence of-V WM. M. MONROE, S. W. SANGsTER. 

